Instructions: Add Your PSA Tests to the Form

Circle the corresponding PSA test value (in ng/mL) in the first column

Write the date in the second column to help you keep track of each test

Instructions: Calibrate and Adjust Your PSA Tests on the Form

See the sections below to learn more about PSA test calibration and adjustment for BPH treatment.On the form for Action 2:

In the row for each PSA test, circle the adjusted value in the appropriate column:

First adjustment column if the test is:

Hybritech calibrated and

No BPH treatment during that test.

Second adjustment column if the test is:

Hybritech calibrated and

BPH treatment during that test.

Third adjustment column if the test is:

WHO calibrated and

No BPH treatment during that test.

Fourth adjustment column if the test is:

WHO calibrated and

BPH treatment during that test.

You may have to ask your physician and/or the lab for PSA test calibrations.Recent tests are usually available if you are persistent.You may have to guess about the calibration of past tests.

PSA Test Calibration - Hybritech and WHO

There are two common PSA calibrations that give different PSA values for the same blood sample. Hybritech calibration refers to the original PSA test approved by the US FDA. Beckman-Coulter bought Hybritech. Many PSA tests supplied in the US are Hybritech calibrated.

​In order to standardize PSA calibration, the WHO developed a different calibration that is often used in many parts of Europe and some other parts of the world. We use Hybritech calibration because it is used by the two most prominent prostate cancer risk calculators and by many studies that we rely on in our cancer risk reports.

Hybritech calibration increases each WHO PSA test by about 25%. For example, a WHO PSA level of 3.2 is roughly comparable to a Hybritech PSA level of 4.0.

​Unfortunately, many lab reports do not identify the calibration of the PSA test value. You may have to ask the lab or your physician for help identifying the calibration of each of your PSA tests. If you can’t determine the calibration with certainty, then you must guess using any clues available.